Photos: Crisis in Syria

UN experts are investigating the alleged use of chemical weapons in Syria as the U.S. and allies prepare for the possibility of a punitive strike against President Assad's regime.

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Free Syrian army fighter fires his weapon

In this image taken from video obtained from the Shaam News Network, which has been authenticated based on its contents and other AP reporting, a Free Syrian army fighter fires his weapon during clashes with government forces, unseen, in Daraya, a suburb of Damascus, Syria, Thursday, Sept. 5, 2013.